The Mayo Protein Core (MPC) Shared Resource was reorganized as the PROTEIN CHEMISTRY AND PROTEOMICS (PCP) Facility in January 2002. The facility has been an important shared resource of the Mayo Clinic Cancer Center (MCCC) since 1992. In the past decade, the PCP shared resource has continued its rapid growth and expansion of core services, and has been an essential resource to MCCC members by its support of a broad diversity of program projects in cancer research. Usage of the resource has grown substantially from 21 members in 1992, to more than 70 current members in 2002. The reorganization of the MPC facility into the PCP shared resource has provided for the development of new services in mass spectrometry to support proteomics based investigations. These services include protein identification by MALDI-TOF mass spectrometry, MS/MS tandem mass spectrometry, and Fourier Transform Ion Cyclotron Resonance (FT-ICR) mass spectrometry. In addition, the PCP resource also provides basic services in protein chemistry, which include solid phase peptide synthesis, protein purification and quantitation, amino acid analysis, chemical protein sequencing, 2-D polyacrylamide gel electrophoresis, and protein molecular modeling. A list of current services provided to MCCC members are:(1) Solid phase peptide synthesis by Fmoc methods; (2) Synthesis of peptidelprotein specific immunogens on KLH or BSA carrier proteins;(3) Edman N-terminal and C-terminal protein sequencing; (4) Quantitative amino acid analysis; (5) Protein purification by reverse phase HPLC and FPLC; (6) Computer-aided analysis of protein sequences for synthetic peptide design; (7) Protein molecular modeling; (8) 1-D and 2-D PAGE of complex protein mixtures; (9) Automated protein digestion and robotic handling of digests for mass spectrometry analysis; (10) Protein identification by MALDI-TOF peptide mass fingerprinting, and (11) Protein identification by peptide sequencing using Ion- Trap LC-MS/MS mass spectrometry. In addition to the services listed above, the continued development of methods in protein mass mappinc by 2D-LC FT-ICR mass spectrometry and the analysis of proteins from cells and biological samples using protein microarrays will also be conducted in the resource.